The captain of the Sewol ferry in South Korea could face a criminal investigation amid unconfirmed claims he abandoned ship after it capsized with over 470 passengers, most of them school students, on board.

The captain of the Sewol ferry in South Korea could face a criminal investigation amid unconfirmed claims he abandoned ship after it capsized with over 470 passengers, most of them school students, on board.

Lee Joon-seok, 69, is being questioned, coastguard officials said, amid reports that he was one of the first to jump to safety from the stricken vessel.

Some survivors told local media Lee was one of the first to be rescued, although none actually saw him leave the ship. The coastguard and the ferry operator declined to comment.

A crew member has since claimed an immediate evacuation order was not issued because officers on the bridge were trying to stabilise the vessel after it started to list amid confusion and chaos.

Oh Yong-seok, 58, said he wasn't sure if the captain's order, given to crew members, was actually relayed to passengers on the public address system. Several survivors also said they did not hear an evacuation order.

The exact cause of the incident has not yet been established and Lee is currently being investigated by police, according to local media. "I am really sorry and deeply ashamed. I don't know what to say," he was shown as saying on local television.

Part of South Korean passenger ship "Sewol" that has been sinking is seen as South Korean maritime policemen search for passengers in the sea off Jindo April 16, 2014. More than 100 people remained missing on Wednesday after a South Korean ferry with 477 people aboard capsized off the country's southwest coast, Yonhap news agency said. REUTERS/Hyung Min-woo/YonhapPart of South Korean passenger ship "Sewol" that has been sinking is seen as South Korean maritime policemen search for passengers in the sea off Jindo April 16, 2014. More than 100 people remained missing on Wednesday after a South Korean ferry with 477 people aboard capsized off the country's southwest coast, Yonhap news agency said. REUTERS/Hyung Min-woo/YonhapAmbulances wait for rescued passengers from a ferry that sank off South Korea's southern coast, at a port in Jindo, south of Seoul, South Korea, Wednesday, April 16, 2014. More than 100 people were still unaccounted Wednesday several hours after a ferry carrying 476, most of them high school students, sank in cold waters off South Korea's southern coast, killing at least two and injuring 14, officials said. (AP Photo/Yonhap, Park Chul-heung)Rescued passengers are escorted by members of a rescue team upon their arrival at a port in Jindo, south of Seoul, South Korea, Wednesday, April 16, 2014. More than 100 people were still unaccounted Wednesday several hours after a ferry carrying 476, most of them high school students, sank in cold waters off South Korea's southern coast, killing at least two and injuring 14, officials said. (AP Photo/Yonhap, Park Chul-heung)A girl rescued by South Korean maritime policemen from a sinking ship "Sewol" in the sea off Jindo, is treated at a port in Jindo April 16, 2014. More than 100 people remained missing on Wednesday after a South Korean ferry with 477 people aboard capsized off the country's southwest coast, Yonhap news agency said. REUTERS/Hyung Min-woo/YonhapRescued passengers from a ferry sinking off South Korea's southern coast, are escorted by rescue teams on their arrival at a port in Jindo, south of Seoul, South Korea, Wednesday, April 16, 2014. More than 100 people were still unaccounted Wednesday several hours after the ferry carrying 476, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/Yonhap, Park Chul-heung)South Korean rescue helicopters fly over a South Korean passenger ship, trying to rescue passengers from the ship in water off the southern coast in South Korea, Wednesday, April 16, 2014. A government office said the passenger ship carrying about 470 people have sent a distress call off the southern coast after it began tittering to one side. (AP Photo/Yonhap)South Korean rescue helicopters fly over a South Korean passenger ship, trying to rescue passengers from the ship in water off the southern coast in South Korea, Wednesday, April 16, 2014. The South Korean passenger ship carrying more than 470 people, including many high school students, is sinking off the country's southern coast Wednesday after sending a distress call, officials said. There are no immediate reports of causalities. (AP Photo/Yonhap)South Korean coast guard officers try to rescue passengers from ferry Sewol in the water off the southern coast near Jindo, south of Seoul, South Korea, Wednesday, April 16, 2014. Dozens of boats, helicopters and divers scrambled Wednesday to rescue more than 470 people, including 325 high school students on a school trip, after the ferry sank off South Korea's southern coast. (AP Photo/Hyung Min-woo, Yonhap)Rescued passengers wrapped in blankets, who were on a sinking ferry "Sewol" in the sea off Jindo, gather at a port in Seogeochado April 16, 2014. More than 100 people remained missing on Wednesday after a South Korean ferry with 477 people aboard capsized off the country's southwest coast, Yonhap news agency said.A passenger is rescued by South Korean maritime policemen from a sinking ship in the sea off Jindo April 16, 2014, in this picture provided by West Regional Headquarters Korea Coast Guard and released by News1. About 160 passengers, including high school students, were plucked to safety on Wednesday in a dramatic rescue from a South Korean passenger ferry "Sewol" sinking with 475 on board, officials said, although at least two people had died. REUTERS/West Regional Headquarters Korea Coast Guard/News1The mother of a passenger who was on a sinking ferry reacts as she finds her son's name in the survivors list at a gym where rescued passengers gather in Jindo April 16, 2014. More than 300 people were missing after the ferry sank off South Korea, the coastguard said on Wednesday, with a three-fold increase in the number of passengers unaccounted for put down to a miscalculation by officials. The ferry Sewol was carrying 477 people, of whom 164 were confirmed rescued, coastguard officials said. Two people were confirmed dead after the ferry listed heavily onto its side and capsized in apparently calm conditions off South Korea's southwest coast. REUTERS/Kim Hong-JiThe mother (R) of a passenger who was on a sinking ferry reacts as she finds her son at a gym where rescued passengers gather in Jindo April 16, 2014. More than 300 people were missing after a ferry sank off South Korea, the coastguard said on Wednesday, with a three-fold increase in the number of passengers unaccounted for put down to a miscalculation by officials. The ferry Sewol was carrying 477 people, of whom 164 were confirmed rescued, coastguard officials said. Two people were confirmed dead after the ferry listed heavily onto its side and capsized in apparently calm conditions off South Korea's southwest coast. REUTERS/Kim Hong-JiThe mother of a passenger who was on a sinking ferry reacts after finding her son's name in the survivors list at a gym where rescued passengers gather in Jindo April 16, 2014. More than 300 people were missing after the ferry sank off South Korea, the coastguard said on Wednesday, with a three-fold increase in the number of passengers unaccounted for put down to a miscalculation by officials. The ferry Sewol was carrying 477 people, of whom 164 were confirmed rescued, coastguard officials said. Two people were confirmed dead after the ferry listed heavily onto its side and capsized in apparently calm conditions off South Korea's southwest coast. REUTERS/Kim Hong-JiRescued passengers cry at a gym where rescued passengers gather in Jindo April 16, 2014. More than 300 people were missing after a ferry sank off South Korea, the coastguard said on Wednesday, with a three-fold increase in the number of passengers unaccounted for put down to a miscalculation by officials. The ferry Sewol was carrying 477 people, of whom 164 were confirmed rescued, coastguard officials said. Two people were confirmed dead after the ferry listed heavily onto its side and capsized in apparently calm conditions off South Korea's southwest coast.REUTERS/Kim Hong-JiIn this photo released by Jeollanamdo via Yonhap News Agency, South Korean rescue team boats and fishing boats try to rescue passengers of a ferry sinking off South Korea's southern coast, in the water off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after a ferry carrying 477, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/Jeollanamdo via Yonhap)In this image taken from video from Mokpo Coast Guard, passengers from a ferry sinking off South Korea's southern coast, are rescued by South Korean Coast guard in the water off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after the ferry carrying 477, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/Yonhap)REFILE - CORRECTION PRONOUN
The mother of a passenger who was on a sinking ferry reacts as she finds her son at a gym where rescued passengers gather in Jindo April 16, 2014. More than 300 people were missing after a ferry sank off South Korea, the coastguard said on Wednesday, with a three-fold increase in the number of passengers unaccounted for put down to a miscalculation by officials. The ferry Sewol was carrying 477 people, of whom 164 were confirmed rescued, coastguard officials said. Two people were confirmed dead after the ferry listed heavily onto its side and capsized in apparently calm conditions off South Korea's southwest coast. REUTERS/Kim Hong-JiIn this photo released by South Korean Navy via Yonhap News Agency, South Korean rescue team boats and fishing boats try to rescue passengers of a ferry sinking off South Korea's southern coast, in the water off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after a ferry carrying 477, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/South Korean Navy via Yonhap)South Korean ferry "Sewol" is seen sinking in the sea off Jindo April 16, 2014, in this picture provided by Korea Coast Guard and released by Yonhap. Almost 300 people were missing after a ferry sank off South Korea on Wednesday, the coastguard said, in what could be the country's biggest peacetime disaster in nearly 20 years. REUTERS/Korea Coast Guard/YonhapSouth Korean ferry "Sewol" is seen sinking in the sea off Jindo April 16, 2014, in this picture provided by Korea Coast Guard and released by Yonhap. Almost 300 people were missing after a ferry sank off South Korea on Wednesday, the coastguard said, in what could be the country's biggest peacetime disaster in nearly 20 years. REUTERS/Korea Coast Guard/YonhapSouth Korean ferry "Sewol" is seen sinking in the sea off Jindo April 16, 2014, in this picture provided by Korea Coast Guard and released by Yonhap. Almost 300 people were missing after a ferry sank off South Korea on Wednesday, the coastguard said, in what could be the country's biggest peacetime disaster in nearly 20 years. REUTERS/Korea Coast Guard/YonhapSouth Korea rescue helicopters fly over to rescue passengers from passenger ship Sewol in the water off the southern coast in South Korea, Wednesday, April 16, 2014. A government office says the South Korean ship carrying about 470 people have sent a distress call off the southern coast after it began tittering to one side. (AP Photo/Yonhap)South Korean ferry "Sewol" is seen sinking in the sea off Jindo April 16, 2014, in this picture provided by Korea Coast Guard and released by Yonhap. Almost 300 people were missing after a ferry sank off South Korea on Wednesday, the coastguard said, in what could be the country's biggest peacetime disaster in nearly 20 years. REUTERS/Korea Coast Guard/YonhapSouth Korean ferry "Sewol" is seen sinking in the sea off Jindo April 16, 2014, in this picture provided by Korea Coast Guard and released by Yonhap. Almost 300 people were missing after a ferry sank off South Korea on Wednesday, the coastguard said, in what could be the country's biggest peacetime disaster in nearly 20 years. REUTERS/Korea Coast Guard/YonhapIn this photo released by South Korea Coast Guard via Yonhap News Agency, South Korean rescue team boats and fishing boats try to rescue passengers of a ferry sinking off South Korea's southern coast, in the water off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after a ferry carrying 459, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/South Korea Coast Guard via Yonhap)South Korean coast guard officers try to rescue passengers from a ferry sinking in the water off the southern coast near Jindo, south of Seoul, South Korea, Wednesday, April 16, 2014. The ferry carrying 459 people, mostly high school students on an overnight trip to a tourist island, sank off South Korea's southern coast on Wednesday, leaving nearly 300 people missing despite a frantic, hours-long rescue by dozens of ships and helicopters. At least four people were confirmed dead and 55 injured. (AP Photo/Yonhap)In this image made from video from South Korean Coast Guard, a passenger of a ferry sinking off South Korea's southern coast is hoisted onto a Coast Guard helicopter off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after a ferry carrying 459, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/South Korean Coast Guard via AP Video)In this image made from video from South Korean Coast Guard, a passenger of a ferry sinking off South Korea's southern coast is rescued and hoisted onto a Coast Guard helicopter off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after a ferry carrying 459, most of them high school students, sank in cold waters off South Korea's southern coast. (AP Photo/South Korean Coast Guard via AP Video)Maritime police search for missing passengers in front of the South Korean ferry "Sewol" which sank at the sea off Jindo April 16, 2014. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/Kim Hong-JiIn this image made from video from South Korean Coast Guard shot from a helicopter, a rescue worker, right in black wetsuit, helps people climb onto a side of a ferry sinking off South Korea's southern coast, off the southern coast near Jindo, south of Seoul, Wednesday, April 16, 2014. Nearly 300 people were still missing Wednesday several hours after a ferry carrying 459, most of them high school students, sank in cold waters off South Korea's southern coast.Maritime police search for missing passengers as the South Korean ferry "Sewol" (C) is seen sinking at the sea off Jindo April 16, 2014. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/Kim Hong-JiIn this photo released by the South Korean Coast Guard via Yonhap News Agency, South Korean coast guard officers rescue passengers from a sinking ferry off the southern coast near Jindo, south of Seoul, South Korea, Wednesday, April 16, 2014. A ferry carrying 459 people, mostly high school students on an overnight trip to a tourist island, sank off South Korea's southern coast on Wednesday, leaving nearly 300 people missing despite a frantic, hours-long rescue by dozens of ships and helicopters. (AP Photo/South Korea Coast Guard via Yonhap)South Korean ferry "Sewol" is seen sinking at the sea off Jindo, as lighting flares are released for a night search, April 16, 2014. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/Kim Hong-JiMaritime police search for missing passengers near the South Korean ferry "Sewol" which sank at the sea off Jindo April 16, 2014. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/Kim Hong-JiMaritime police search for missing passenger as lighting flares are released for a night search, following the sinking of South Korean ferry "Sewol" at the sea off Jindo April 16, 2014. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/Kim Hong-JiRelatives wait for their missing loved ones at a port in Jindo, South Korea, Wednesday, April 16, 2014. A ferry carrying 459 people, mostly high school students on an overnight trip to a tourist island, sank off South Korea's southern coast on Wednesday, leaving nearly 300 people missing despite a frantic, hours-long rescue by dozens of ships and helicopters. (AP Photo/Ahn Young-joon)A maritime officer (in black) rescues passengers onboard South Korean ferry "Sewol" which capsized off Jindo April 16, 2014 in this picture provided by West Regional Headquarters Korea Coast Guard and released by News1. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/West Regional Headquarters Korea Coast Guard/News1Part of the capsized South Korean ferry "Sewol" (C) is seen in the sea off Jindo April 16, 2014 in this picture provided by South Korean Navy and released by Yonhap. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/South Korean Navy/YonhapA relative waits for their missing loved one at a port in Jindo, South Korea, Wednesday, April 16, 2014. A ferry carrying 459 people, mostly high school students on an overnight trip to a tourist island, sank off South Korea's southern coast on Wednesday, leaving nearly 300 people missing despite a frantic, hours-long rescue by dozens of ships and helicopters. (AP Photo/Ahn Young-joon)Maritime officers (in black) try to rescue passengers (in orange coloured life vests) onboard South Korean ferry "Sewol" which capsized off Jindo April 16, 2014 in this picture provided by West Regional Headquarters Korea Coast Guard and released by News1. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/West Regional Headquarters Korea Coast Guard/News1Part of the capsized South Korean ferry "Sewol" (C) is seen in the sea off Jindo April 16, 2014 in this picture provided by South Korean Navy and released by Yonhap. Almost 300 people were missing after a ferry capsized off South Korea on Wednesday, despite frantic rescue efforts involving coastguard vessels, fishing boats and helicopters, in what could be the country's biggest maritime disaster in over 20 years. REUTERS/South Korean Navy/YonhapRelatives of passengers of a sunken ship wrapped in blankets look toward the sea at Jindo port, South Korea, Wednesday, April 16, 2014. The ferry carrying 459 people, mostly high school students on an overnight trip to a tourist island, sank off South Korea's southern coast on Wednesday, leaving nearly 300 people missing despite a frantic, hours-long rescue by dozens of ships and helicopters. (AP Photo/Ahn Young-joon)

At a press conference today, the Chief of the West Regional Headquarters of the South Korean Coastguard Kim Soo-hyun said he would approve civilian divers who wanted to assist the search, providing there was "trust" between them and official search teams.

Speaking today, South Korean President Park Geun-hye urged rescue teams to "hurry" as time was running out in the hunt for survivors

Earlier, relatives waiting desperately for news of their loved ones reacted with fury when Prime Minister Chung Hong-won visited a gymnasium in Jindo, a nearby island, with some throwing water at him.

Another relative hit a government official briefing those who had gathered at the gym on the rescue operation following reports that passengers had been told to stay on the ship as it sank.

Grieving parents also accused rescue teams of being slow to react and of providing a lack of information.

As frustration grew, some parents of missing school children hired their own boat on Wednesday night. They appeared to blame the government of President Park Geun-hye and rescue officials for not making a big enough effort.

"Since the government refused to take us to the scene, 11 parents chipped in 61,000 won ($58.79) each to hire a boat and took a reporter and a diver. But there was no rescue operation going on," said one father said.

Earlier, rescue teams hammered on the hull of the upturned, mostly submerged vessel, hoping for a response from anyone trapped inside, but they heard nothing, local media reported.

Some 325 school children from the Danwon High School in Ansan, a Seoul suburb, were among the passengers on board the vessel, which was heading to the popular tourist island of Jeju. Nine people have been found dead and at least 280 are still missing.

Teams of divers fought rising winds, strong waves and murky waters through the night to locate those missing after the MV Sewol sank off the south-western coast of South Korea.

The dramatic rescue operation began two hours after the ship started listing severely and the ferry filled with water. Several survivors said passengers were told to remain where they were by on board announcements.

Cha Eun-ok, who was on the deck taking photographs at the time, said an “on-board announcement told people to stay put... people who stayed are trapped”.